NO. 3 CAMBRIAN AND OZARKIAN TRILOBITES IIQ 



slope of the side toward the glabella is much steeper than the one on 

 the outside. Surface covered with fine, irregular lines. 



The frontal border is quite distinct. It is wide in reality but appears 

 narrower than it is, due to the fact that it first rises sharply from the 

 frontal portion of the dorsal furrow into a ridge, then drops off 

 very steeply, which results in the unusual appearance of this trilobite. 

 Viewed from the front there is only a vertical band. In some speci- 

 mens a narrow, poorly defined rim seems to be indicated. 



Free cheeks unknown. 



About nine segments of the thorax are preserved on one specimen. 

 The pleural furrows are fairly deep and seem to divide the pleurae 

 into two approximately equal portions. 



Pygidium unknown at present, but futher investigation of the large 

 collections from the type locality may result in its determination as 

 well as of the free cheeks. 



Genotype. — Utia curio Walcott. 



Stratigraphic range. — Middle Cambrian : Spence shale member of 

 the Ute formation. 



Geographic distribution. — In a ravine 15 miles (24.2 km.) west 

 of Montpelier, Bear Lake County, Idaho. 



Observations. — The characters of the type species of the genus as 

 far as known are given in the specific description of Utio curio 

 Walcott. The rectangular glabella, tumid frontal limb, and its great 

 downward extension in front give an assemblage of characters 

 unknown to me in any other trilobite. The small palpebral lobe and 

 strong ocular ridge with the rectangular glabella suggest Inouyia capax 

 Walcott,^ but the downward extension of the frontal border is unlike 

 anything referred to Inouyia. 



The only known species is a small one, indicating a size for the 

 genus about the same as for Agraulos and Inouyia. 



UTIA CURIO Walcott 



Plate IS, figs. 11-14 



Utia curio Walcott, 1924, Smithsonian Misc. Coll., Vol. 75, No. 2, p. 60, pi. 13, 

 fig. 3. 



Dorsal shield. — Dorsal shield small, regularly elliptical in outline, 

 the breadth more than two-thirds the length. Axial lobe moderately 

 wide, strongly convex, rising well above the pleural lobes which were 



^Research in China, Carnegie Inst, of Washington, Vol. 3, 1913, p. 151, 

 pi. 14, f. II. 



